feat(cdk/tree): deprecate the TreeControl APIs

Author: BobobUnicorn

src/cdk/tree/control/base-tree-control.ts

@@ -9,7 +9,11 @@ import {SelectionModel} from '@angular/cdk/collections';
 import {Observable} from 'rxjs';
 import {TreeControl} from './tree-control';
 
-/** Base tree control. It has basic toggle/expand/collapse operations on a single data node. */
+/**
+ * Base tree control. It has basic toggle/expand/collapse operations on a single data node.
+ *
+ * @deprecated Use one of levelAccessor or childrenAccessor
+ */
 export abstract class BaseTreeControl<T, K = T> implements TreeControl<T, K> {
   /** Gets a list of descendent data nodes of a subtree rooted at given data node recursively. */
   abstract getDescendants(dataNode: T): T[];

src/cdk/tree/control/flat-tree-control.ts

@@ -13,7 +13,11 @@ export interface FlatTreeControlOptions<T, K> {
   trackBy?: (dataNode: T) => K;
 }
 
-/** Flat tree control. Able to expand/collapse a subtree recursively for flattened tree. */
+/**
+ * Flat tree control. Able to expand/collapse a subtree recursively for flattened tree.
+ *
+ * @deprecated Use one of levelAccessor or childrenAccessor
+ */
 export class FlatTreeControl<T, K = T> extends BaseTreeControl<T, K> {
   /** Construct with flat tree data node functions getLevel and isExpandable. */
   constructor(

src/cdk/tree/control/nested-tree-control.ts

@@ -14,7 +14,11 @@ export interface NestedTreeControlOptions<T, K> {
   trackBy?: (dataNode: T) => K;
 }
 
-/** Nested tree control. Able to expand/collapse a subtree recursively for NestedNode type. */
+/**
+ * Nested tree control. Able to expand/collapse a subtree recursively for NestedNode type.
+ *
+ * @deprecated Use one of levelAccessor or childrenAccessor
+ */
 export class NestedTreeControl<T, K = T> extends BaseTreeControl<T, K> {
   /** Construct with nested tree function getChildren. */
   constructor(

src/cdk/tree/control/tree-control.ts

@@ -12,6 +12,8 @@ import {Observable} from 'rxjs';
  * Tree control interface. User can implement TreeControl to expand/collapse dataNodes in the tree.
  * The CDKTree will use this TreeControl to expand/collapse a node.
  * User can also use it outside the `<cdk-tree>` to control the expansion status of the tree.
+ *
+ * @deprecated Use one of levelAccessor or childrenAccessor
  */
 export interface TreeControl<T, K = T> {
   /** The saved tree nodes data for `expandAll` action. */